I actually don't mind calling Uncharted a platformer because a large amount of that game is focused on platforming.  I would rather personally just call it action/adventure but I don't mind people lumping that into a platformer.

As for inFamous, I've never played it but I don't know if I would count open world movement as a platformer.

Super Mario Galaxy.

That was an easy one

In a platformer, you jump between platforms and you die if you miss the jump. That's not happening in PoP. Might as well have auto jump like Zelda.

You don't die in Braid or LBP planet either. 

Elika saving you is just the allusion of death and the skipping of the game over screen. A welcome change. (if she saves you, it would considered dying)

That's the stupidest definition of a platformer I've ever heard.

In such case, please define what's a platformer and a third person adventure game.

I think matters more on what the focus of the game is.

In Mario, the focus is on the platforming rather than the combat. (making it a platformer, not an action game)

But the recent focus of Ratchet & Clank has not been platforming. Would you call it a platformer? In the same regard, is platforming the focus of Uncharted and Infamous?

Eh, I think the focus of Ratchet is still platforming.

I'm sure why anyone thought Infamous was a platformer though. It's a sandbox game.

Uncharted is a wash for me. While platformer is a huge part, there is a ton of fights.